Automatic transportation of pallets of goods

ABSTRACT

A layer pick system optimizes usage of a layer picker gantry or robotic arm by arranging and/or displacing the gantry or arm in optimal locations with respect to one or more groups of pallets, and/or by grouping pallets by their attributes and arranging the same group of pallets close to each other. In some implementations, a plurality of pallets is categorized into multiple groups by different velocities.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.16/843,772, titled “AUTOMATIC ASSEMBLY OF PALLETS OF GOODS,” which wasfiled on Apr. 8, 2020, which claims priority to U.S. Provisional PatentApplication No. 62/830,904, titled “AUTOMATIC ASSEMBLY OF PALLETS OFGOODS,” which was filed on Apr. 8, 2019; to U.S. Provisional PatentApplication No. 62/831,695, titled “AUTOMATIC TRANSPORTATION OF PALLETSOF GOODS,” which was filed on Apr. 9, 2019; to U.S. Provisional PatentApplication No. 62/880,638, titled “AUTOMATIC TRANSPORTATION OF PALLETSOF GOODS,” which was filed on Jul. 30, 2019; and to U.S. ProvisionalPatent Application No. 62/880,640, titled “CONTROLLING AUTOMATED PALLETMOVERS,” which was filed on Jul. 30, 2019, the entire contents of eachof which are hereby incorporated herein by reference.

TECHNICAL FIELD

This document generally describes technology for automaticallyassembling multiple pallets of goods.

BACKGROUND

Layer picking is a method of picking and moving layers of goods from onepallet to another. Pallets are generally flat transport structures thatsupport goods in a stable manner and that are adapted to fit forkliftsand/or other devices/machines to move the pallets. Layer picking istypically performed at a facility to which first pallets bearinghomogenous or similar goods are delivered. A layer picking apparatus,such as a forklift or a conveyor belt, is operated to locate a firstpallet bearing target goods, pick a layer of target goods from thelocated first pallet, and move the layer onto a target pallet so thatthe target pallet bears the target goods with other goods. The targetpallet can then be moved to a storage facility or discharged to fulfillan order.

SUMMARY

Some embodiments described herein include a system for automaticallyassembling multiple pallets of goods using a first device configured topick layers of goods from pallets and move them over other palletswithin an assembly area. In addition, the system includes a seconddevice configured to move pallets of goods into, from, and/or around theassembly area. The first device can be, for example, a gantry or roboticarm configured to pick and move layers of goods over pallets. The seconddevice can be, for example, automated guided vehicles that automaticallynavigate and are capable of picking up, moving, and dropping offpallets.

Various algorithms can be used to manage and optimize the assembly ofmultiple pallets within an assembly area. For example, algorithms areconfigured to define grids on an assembly area so that pallets can beselectively placed in a gridded arrangement on the assembly area. Suchalgorithms are configured to drive the first device (e.g., a layerpicker gantry or robotic arm) to efficiently relocate layers of goodsover pallets on the assembly area. Any of a variety of techniques couldbe used to optimize such operations, like swarm robotic techniques,which can be used to speed up pallet movements and reduce the time ittakes to move the pallets. Dynamic paths can be generated to open and/orclose routes to provide for optimized movements. The gantry area can bespace optimized whereas the areas around it, such as buffer areas, canbe speed optimized.

In addition, algorithms are configured to optimize usage of the firstdevice (e.g., a layer picker gantry or robotic arm) by arranging and/ordisplacing the first device in optimal locations with respect to one ormore groups of pallets, and/or by grouping pallets by their attributesand arranging the same group of pallets close to each other. In someimplementations, a plurality of pallets is categorized into multiplegroups by different velocities (or velocity ranges). A velocity of apallet can indicate how fast the pallet is palletized or depalletized inan assembly area. Alternatively, a velocity of a pallet can indicate howlong the pallet stays in an assembly area (or on its location in theassembly area) before the pallet is removed from the assembly area (orbefore it is relocated in the assembly area). The groups of palletshaving different velocities (or velocity ranges) are arranged ondifferent zones in an assembly area with respect to the first device.For example, slow moving pallets can be arranged in a first zone, whilefast moving pallets can be arranged in a second zone around the firstzone so that the fast moving pallets are located around a periphery ofthe first device. This arrangement of pallets can promote fast movingpallets to be removed from the assembly area after palletizing ordepalletizing is complete. The first zone can be located at a center ofthe assembly area and the second zone can be located to surround thefirst zone. In some implementations, the first device can be located inthe first zone. In other implementations, the first device uses alocation (e.g., a center) of the first zone as a primary location orreference location for its movement throughout the assembly area. Inaddition, a third zone may be provided for slower (or absolutely slow)moving pallets that the assembly device does not have to reach as oftenand/or fast as it does for fast or slow moving pallets. The third zonecan be located around a periphery of the assembly area or an area of theassembly area away from the first device.

In addition or alternatively, algorithms can be used to drive the seconddevice (e.g., automated guided vehicles) to automatically navigatewithin and/or around the assembly area. Such algorithms can optimize away that the second device picks up a pallet of goods from a supplyarea, and moves and places the pallet onto the assembly area. Forexample, the algorithms enable the second device to place the pallet onone of the grids defined in the assembly area in such a way that thesecond drive can efficiently perform layer picking from/onto all palletsarranged in the assembly area. The algorithms can further optimize a waythat the second device picks up a pallet from the assembly area andmoves the pallet to an output area (e.g., a discharge area). Someembodiments of the algorithms can be designed to place pallets in agridded arrangement on an assembly area so as to make every palletaccessible by the second device on the assembly area. For example,pallets are selectively placed in the grids of an assembly area suchthat at least one path to any of the pallets is available for a seconddevice entering and exiting the assembly area.

The technologies described herein may provide one or more of thefollowing advantages. The system for assembling pallets of goodsdescribed herein can replace conventional pallet transportation devices,such as conveyor belt systems and forklifts, by automated guidedvehicles to intelligently move pallets of goods into and from anassembly area, thereby reducing operational costs. Pallets of goods aretypically transported using multiple conveyor belt systems that arerouted from a supply area to an assembly area, and from the assemblyarea to an output area. Complexity of conveyor belt systems (e.g., a mixof straight and curved configurations) requires costly installation.Further, once installed, conveyor belt systems are fixed and has limitedflexibility in modifying paths into and from the assembly area.Moreover, forklifts are human-driven vehicles relying manual operationwhich is cost-intensive and less optimized. In contrast, automatedguided vehicles can provide cost efficient solutions for transportingpallets, and give much more freedom of movement because they are free tomove in any available direction and along any available path into andfrom the assembly area. Further, some algorithms permit for pallets tobe grouped by same or similar attributes (e.g., velocity) and arrangedso that the same groups of pallets are arranged close to each other forefficient palletizing or depalletizing operation of a assembly device(e.g., a layer picker gantry or robotic arm). Such algorithms canminimize an overall travel distance and movement of the assembly devicewith respect to pallets in the assembly area, as well as permit for apallet transportation device (e.g., automated guided vehicles) to carrypallets into or out of the assembly area along shorter routes and intime-saving manners.

In addition or alternatively, some embodiments described herein includea system for transporting pallets in a warehouse using automated guidedvehicles, such as in an area between a pallet loading/unloading area anda pallet storage area in the warehouse. A warehouse includes a palletloading/unloading area where trucks are pulled over so that pallets areunloaded from, or loaded to, the trucks. A warehouse further includes apallet storage area configured to store pallets in a dense arrangement.For example, the pallet storage area may include multiple-story rackswith an elevator system operable to convey pallets to/from differentfloors of the racks. Typically, a conveyor belt system is used totransport pallets between the pallet loading/unloading area and thepallet storage area. A conveyor belt system includes a complex layout ofconveyor belts which has many connection points between conveyor beltsand many bottle neck areas where multiple conveyor belts are connectedto one conveyor belt. The conveyor belt system operates to conveymultiple pallets from different start locations to different endlocations at the same time. For example, the pallet loading/unloadingarea includes a plurality of decks from/to which pallets that areloaded/unloaded to/from truck are carried by workers. Further, thepallet racks have a plurality of columns and rows in multiple levels(heights) from/to which pallets are transported using differentelevators. Such a complex conveyor belt system often results in cloggingwhen a large number of pallets are conveyed at the same time betweendifferent start locations and end locations. For example, pallets whichtravel deep in the conveyor belt system can be stuck with other palletsmoving along long routes of conveyor belts. Moreover, once the conveyorbelts are set up, they are less flexible in creating and modifying pathsalong which pallets can be carried.

The pallet transportation system described herein uses automated guidedvehicles that replace the complex conveyor belt system installed to movepallets in a warehouse. Automated guided vehicles can automaticallynavigate and are capable of picking up, moving, and dropping offpallets. Algorithms are configured to optimize operation of automatedguided vehicles in a warehouse. Algorithms can be used to determineoptimal routes of each automated guided vehicle from a start location toan end location. For example, algorithms can be configured to optimizeor minimize the number of cross-overs of the routes taken by automatedguided vehicles. In addition or alternatively, algorithms can beconfigured to optimize the timing of operation of respective automatedguided vehicles, thereby reducing the likelihood of collision betweenvehicles. In addition or alternatively, algorithms can be configured tooptimize or maximize the speed of respective automated guided vehicles.In addition or alternatively, algorithms can be configured to optimizeor minimize the time required to complete a particular project of movingpallets in a warehouse.

The pallet transportation system described herein can replaceconventional pallet transportation devices, such as conveyor beltsystems, by automated guided vehicles to intelligently move pallets ofgoods between different locations in a warehouse, thereby optimizingroutes and/or timing of pallet transportation, avoiding collisionbetween different pallets being transported, reducing a transportationtime, and reducing operational costs. Further, the pallet transportationsystem can provide great flexibility in managing pallets in a warehousebecause automated guided vehicles allow a large number of possible pathsbetween a particular set of start and end locations, as opposed to aconveyor belt system that provides a limited number of possible routesbetween the start and end locations. The pallet transportation systemcan provide redundancy in route selection by allowing a large number ofroute options between particular start and end positions. An optimalroute can be selected from such multiple route options to meet differentcriteria required in managing pallets in a warehouse.

Particular embodiments described herein include a method forautomatically assembling pallets of goods. The method may include one ofmore of the following operations: driving a first automated pallet moverto move to a supply area in which a plurality of pallets are unloadedand positioned; identifying a target supply pallet from the plurality ofpallets in the supply area; controlling the first automated pallet moverto grasp the target supply pallet; determining a target supply cell onan assembly area, the assembly area defining a plurality of cellsincluding the target supply cell; determining an optimal inbound pathfor the first automated pallet mover to reach the target supply cell onthe assembly area; driving the first automated pallet mover to move tothe target supply cell along the optimal inbound path on the assemblyarea; controlling the first automated pallet mover to place the targetsupply pallet on the target supply cell of the assembly area;controlling a layer picking apparatus to palletize and/or depalletizebetween the target supply pallet and a target output pallet, the targetoutput pallet arranged on a target output cell of the assembly area;determining an optimal outbound path for a second automated pallet moverto reach the target output cell on the assembly area; driving the secondautomated pallet mover to move to the target output cell along theoptimal outbound path on the assembly area; controlling the secondautomated pallet mover to grasp the target output pallet; and drivingthe second automated pallet mover to exit the assembly area along theoptimal outbound path.

In some implementations, the system can optionally include one or moreof the following features. The layer picking apparatus may include alayer picking gantry and/or a robotic arm. The first automated palletmover and the second automated pallet mover may include automatedvehicles. The first automated pallet mover may be the same as the secondautomated pallet mover. The plurality of cells may be defined in agridded arrangement on the assembly area. The target supply cell may bedetermined such that the target supply cell is always accessible by thefirst automated pallet along at least one path defined through thegridded arrangement of the plurality of cells on the assembly area. Thetarget supply cell for the supply pallet and the target output cell forthe output pallet may be determined such that every pallet is alwaysaccessible along at least one path defined through the griddedarrangement of the plurality of cells on the assembly area. Determininga target supply cell on an assembly area may include determining thatthe target supply pallet is a first pallet having one or more layers ofgoods to be moved onto or out from the first pallets less than a firstthreshold number of times per a predetermined period of time, anddetermining the target supply cell in a first zone of the assembly area.Determining a target supply cell on an assembly area may includedetermining that the target supply pallet is a second pallet having oneor more layers of goods to be moved onto or out from the second palletsmore than the first threshold number of times per the predeterminedperiod of time, and determining the target supply cell in a second zoneof the assembly area, the first zone being at least partially surroundedby the second zone. Determining a target supply cell on an assembly areamay include determining that the target supply pallet is a third pallethaving one or more layers of goods to be moved onto or out from thethird pallets less than a second threshold number of times per thepredetermined period of time, the second threshold number of times beingsmaller than the first threshold number of times; and determining thetarget supply zone in a third zone of the assembly area, the second zonebeing at least partially surrounded by the third zone.

Particular embodiments described herein include a method forautomatically assembling pallets of goods. The method may include one ormore of the following operations: determining a first zone and a secondzone in an assembly area, the first zone being at least partiallysurrounded by the second zone; placing first pallets in the first zone,the first pallets having one or more layers of goods to be moved onto orout from the first pallets less than a first threshold number of timesper a predetermined period of time; placing second pallets in the secondzone, the second pallets having one or more layers of goods to be movedonto or out from the second pallets more than the first threshold numberof times per the predetermined period of time; and controlling a layerpicking apparatus to palletize or depalletize among the first palletsand the second pallets.

In some implementations, the system can optionally include one or moreof the following features. The method may include determining a thirdzone in the assembly area, placing third pallets in the third zone, andcontrolling the layer picking apparatus to palletize or depalletizeamong the first pallets, the second pallets, and the third pallets. Thesecond zone may be at least partially surrounded by the third zone. Thethird pallets may have one or more layers of goods to be moved onto orout from the third pallets less than a second threshold number of timesper the predetermined period of time. The second threshold number oftimes may be smaller than the first threshold number of times. Placingfirst pallets in the first zone may include driving one or moreautomated pallet movers to move the first pallets from a storage area tothe first zone of the assembly area, and driving the automated palletmovers to move the second pallets from the storage area to the secondzone of the assembly area. The third zone may be arranged on a peripheryof the assembly area. The method may include driving one or moreautomated pallet movers to move the third pallets between the third zoneof the assembly area and a buffer area, the buffer area disposed atleast partially around the assembly area. The automated pallet moversmay move along straight routes between the third zone of the assemblyarea and the buffer area. The assembly area may include a plurality ofcells in a gridded arrangement. The layer picking apparatus may includea layer picking gantry. The automated pallet movers may include AGVand/or SDV. The method may include driving the automated pallet moversto remove the first pallets from the first zone of the assembly area,and driving the automated pallet movers to remove the second palletsfrom the second zone of the assembly area.

The details of one or more implementations are set forth in theaccompanying drawings and the description below. Other features andadvantages will be apparent from the description and drawings, and fromthe claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic illustration of an example system forautomatically assembling multiple pallets of goods.

FIG. 2 illustrates a schematic plan view of an example assembly area.

FIG. 3 depicts an example system for automatically assembling pallets ofgoods in an example warehouse environment.

FIG. 4A depicts another example system for automatically assemblingpallets of goods in an example warehouse environment.

FIG. 4B illustrates an example system for automatically assemblingpallets of goods in an example warehouse environment.

FIG. 4C illustrates an example system for automatically assemblingpallets of goods in an example warehouse environment.

FIG. 5 depicts another example system for automatically assemblingpallets of goods in an example warehouse environment.

FIG. 6 depicts an example pallet picking area that can be used withautomated vehicles and a layer picking gantry device.

FIGS. 7A-F are flowcharts of example techniques that can be used as partof an automated control system for pallet assembly using automatedvehicles and automated layer picking devices.

FIGS. 8A-C depict example systems to control operation of the automatedvehicles using stereoscopic vision.

FIG. 9 is a block diagram of example computing devices that may be usedto implement the devices, systems, and methods described in thisdocument.

FIG. 10 depicts an example pallet transportation system in a warehouse.

FIG. 11 depicts another example pallet transportation system in awarehouse.

FIG. 12 is a flowchart of an example technique that can be used as partof the pallet transportation system of FIGS. 10 and 11.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

FIG. 1 is a schematic illustration of an example system 100 forautomatically assembling multiple pallets of goods. The system 100 maybe implemented in a warehouse 102, such as a storage warehouse, adistribution center, a retail warehouse, a cold storage warehouse, anoverseas warehouse, a packing warehouse, a railway warehouse, a canalwarehouse, and other types of warehouses or facilities. The system 100includes several areas for arranging pallets, such as a supply area 104,an assembly area 106, an output area 108, and a case pick area 109. Insome implementations, two or more of the areas 104, 106, 108, and 109can be at least partially overlap.

The supply area 104 provides an area in which pallets 110 aretemporarily placed until they are transported to the assembly area 106.In this document, the pallets 110 arranged on the supply area 104 may bealso referred to as supply pallets 110A. The supply area 104 may be apredetermined area of the warehouse 102, and/or another warehouse remotefrom the warehouse 102 of the system 100. In some implementations,trucks and other vehicles can transport the pallets 110 to the supplyarea 106.

The assembly area 106 provides an area in which goods supported onpallets 110 (including 110A and 110B) are palletizing and depalletizing.For example, layers of goods supported on pallets 110 in the assemblyarea 106 can be moved and/or rearranged between the pallets 110. Inaddition or alternatively, layers of goods supported on the pallets 110in the assembly area 106 can be moved to empty pallets 110 in theassembly area 106 to create new pallets of goods.

For example, when the supply pallets 110A are delivered from the supplyarea 104 to the assembly area 106, layers of goods on the supply pallets110A can be picked up, and moved onto one or more other pallets whichwill be discharged to the output area 108. Such other pallets may bealso referred to herein as output pallets 110B in this document.

The system 100 includes a layer picking apparatus 120 configured tolift, move, and drop layers of goods over pallets, thereby buildingdesired pallets bearing layers of goods from different pallets. Thelayer picking apparatus 120 can be configured to automatically identifya pallet of desired goods, lift one or more layers of goods from thepallet, and move and drop the layers onto a target pallet.

The layer picking apparatus 120 can include a layer picking gantry 122as illustrated in FIG. 1. The layer picking gantry 122 is built over theassembly area 106 and includes a layer grasping tool 124 configured tograsp and release one or more layers of goods using, for example,clamping and/or suction force. The layer picking gantry 122 includes atool drive mechanism configured to move the layer grasping tool 124vertically up and down (e.g., along direction D1 along axis Z), move italong a width of the assembly area (e.g., along direction D2 along axisX), and move it along a length of the assembly area (e.g., alongdirection D3 along axis Y).

Alternatively or in addition, the layer picking apparatus 120 caninclude a robotic arm having a layer grasping tool at its distal end.The robotic arm can be positioned at a fixed location on the assemblyarea 106, such as a center of the assembly area 106, from which therobotic arm can reach all or some of pallets arranged therearound in theassembly area 106. Alternatively, the robotic arm can be configured tobe movable along one or more guide rails, or freely, in the assemblyarea 106.

Alternatively or in addition, any other suitable devices for automatedlayer picking operations can be used for the layer picking apparatus120. For example, in some implementations, the layer picking apparatus120 can include automated vehicles dedicated or specifically designedfor layer picking.

The output area 108 provides an area in which the pallets 110, such asoutput pallets 110B, which have been transported out from the assemblyarea 106 are arranged. The output area 108 may be a predetermined areaof the warehouse 102, and/or another warehouse remote from the warehouse102 of the system 100. In some implementations, trucks and othervehicles can transport the pallets 110 (e.g., output pallets 110B) outfrom the output area 108.

The case pick area 109 provides an area in which case picking may beperformed. Cases can be transported from and into, or relocated within,the case pick area 109 manually and/or using automated equipment, suchas conveyor belt systems, automated vehicles (e.g., AGVs and/or SDVs),gantries, robotic arms, and other suitable vehicles (e.g., forklifts,etc.) or devices.

Referring still to FIG. 1, the system 100 can further include one ormore pallet movers 140 configured to pick up, carry, and drop pallets110. The pallet movers 140 can be configured to automatically movewithin the warehouse 102, such as within the supply area 104, betweenthe supply area 104 and the assembly area 106, within the assembly area106, between the assembly area 106 and the output area 108, and withinthe output area 108.

In some implementations, the pallet movers 140 include automated guidedvehicles (automated vehicles). Examples of such automated vehiclesinclude automated guided vehicles (AGVs) and self-driving vehicles(SDVs). For example, an automated vehicle can be configured to be an AGVwhich is a portable robot that can automatically move and performseveral tasks by following predetermined instructions with minimal or nohuman intervention. An automated vehicle are computer-controlled,unmanned electric vehicle controlled by pre-programmed software to movepallets around a warehouse. Automated vehicles are freely moveable.Alternatively or in addition, automated vehicles can work with guidancedevices, such as magnetic tapes, beacons, barcodes, or predefined laserpaths that allow the automated vehicles to travel on fixed or variablepaths in a controlled space. Example guidance devices include markedlines or wires on the floor, and/or guidance by using radio waves,vision cameras, magnets, lasers, and/or other technologies fornavigation. Automated vehicles can include lasers and/or sensorsconfigured to detect obstacles in its path and trigger them to stopautomatically.

In addition or alternatively, automated vehicles can be configured to beSDVs which autonomously move and perform functions in a warehouse. Forexample, automated vehicles are configured to automatically makedecisions when faced with new or unexpected situations. Automatedvehicles are further configured to learn as they encounter newsituations. Automated vehicles can be configured to operate withoutdirect driver input or pre-configured scripts to control steering,acceleration, and braking. Automated vehicles can use laser-basedperception and navigation algorithms to dynamically move through thearea in a warehouse. In some implementations, automated vehicles includeonboard intelligence to adapt to changing environments. Further, machinelearning capabilities can be used to enable automated vehicles to becomeefficient and accurate as they encounter new or unexpected situations.Data can be collected for machine learning which can update a warehousemap (which maps the warehouse and includes zones and points of interest)with learned parameters. Automated vehicles can be configured to learnwhich routes are the fastest and take optimal paths, even withinunpredictable environments. Multiple automated vehicles cancollaboratively interact with other automated vehicles. In someexamples, automated vehicles do not require external infrastructure fornavigation, making implementation hassle-free and highly scalable.Automated vehicles can be configured to detect, avoid, and dynamicallymove around obstacles (including other automated vehicles) to continueto destination, reducing downtime. Parameters associated with automatedvehicles can be customized to navigate through aisleways, personnelzones, narrow corridors, and other regions.

Referring still to FIG. 1, the system 100 includes a computing device150 for controlling pallet assembly and/or transportation in thewarehouse 102. Although a single computing device 150 is illustrated andprimarily described herein, multiple computing devices can be configuredto perform same or similar functions. The computing device 150 isconfigured to communicate with the layer picking apparatus 120 (e.g., alayer picker gantry or robotic arm) and/or the one or more pallet movers140 (e.g., automated guided vehicles), and manage and optimizetransportation and/or assembly of pallets in the warehouse 102.

FIG. 2 illustrates a schematic plan view of an example assembly area200. In some implementations, the assembly area 200 can represent theassembly area 106 of FIG. 1. The assembly area 200 can be managed by oneor more computing devices, such as the computing device 150, thecomputing device of the layer picking apparatus 120, and/or thecomputing device of each pallet mover 140 of FIG. 1, which run one ormore algorithms for managing and optimizing the assembly of multiplepallets within the assembly area 200. Various algorithms can be used foroptimization of pallet transportation and/or assembly in the assemblyarea 200 (and/or a temporary pallet area 270 as described below).Example algorithms are described below, for example, with regard toFIGS. 7A-F.

In some implementations, such algorithms can define cells 220 in theassembly area 200 that are configured to permit for pallets 230(including 230A-I) to be placed thereon. In the illustrated example, thecells 220 are defined as grids and arranged in a gridded arrangement.Alternatively or in addition, other shapes, such as circles andpolygons, are possible for the cells 220.

The algorithms are configured to drive a first device, such as the layerpicking apparatus 120, to relocate (e.g., palletizing and depalletizing)layers of goods from one pallet to another in the assembly area 200. InFIG. 2, for example, the first device can lift a layer of goods from apallet 230C, move the layer, and place it on a pallet 230D (process240A). Similarly, the first device can move a layer of goods from apallet 230E to a pallet 230F (process 240B), and a layer of goods from apallet 230G to a pallet 230B (process 240C).

The algorithms can further be configured to drive a second device, suchas one or more pallet movers 140, to automatically navigate withinand/or around the assembly area 200. The algorithms are configured tooptimize a way that the second device picks up a pallet from a supplyarea (e.g., the supply area 104), and moves and places the pallet ontothe assembly area 200. For example, the algorithms can enable the seconddevice to determine an optimal path to reach a target cell to place apallet on the assembly area and move to the target cell with the pallet.In addition or alternatively, the algorithms can enable the seconddevice to place the pallet 230 (including 230A-I) on one of the cells220 defined in the assembly area in such a way that the second drive canefficiently perform layer picking from/onto some or all pallets arrangedin the assembly area. The algorithms can be configured to drive thesecond device to avoid interfering with the operation of the firstdevice (e.g., the layer picking apparatus 120), so that the first devicecan continue to operate for palletizing and depalletizing the palletswhile the second device moves in the assembly area 200. Further, thealgorithms can determine one of the cells 220 to place a particularpallet 230, which will allow a shortest entering route, optimal layerpicking, and/or avoiding interference of the second device with theoperation of the first device.

In addition or alternatively, the algorithms can optimize a way that thesecond device picks up a pallet 230 (including 230A-I) from the assemblyarea 200 and moves the pallet 230 to an output area (e.g., the outputarea 108). For example, the algorithms can enable the second device todetermine an optimal path to access a target pallet and remove it fromthe assembly area 200. In addition or alternatively, the algorithms candrive the second device to access and move the pallet withoutintervening the movement of the first device performing layer picking.The algorithms can further permit for the second device to enter theassembly 200, lift the pallet, move it out of the assembly area 200,along the optimal path. In FIG. 2, for example, paths 250A-C aredetermined as a shortest exit route for a second device 210 (e.g., thepallet mover 140) to access the pallet 230A and remove it from theassembly area 200. Further, the paths 250A-C can be determined such thatthe movement of a second device 210 does not interfere with theoperation of the first device on the assembly area 200 during themovement of the second device 210.

In addition or alternatively, the algorithms can be designed to placepallets in the cells 220 on the assembly area 200 so as to make everypallet accessible by the second device on the assembly area 200. Forexample, all pallets are placed in the cells 220 of the assembly area200 such that at least one path to any of the pallets is available forthe second device entering and exiting the assembly area 200.

In some implementations, the assembly area 200 can be accompanied by atemporary pallet area 270. The temporary pallet area 270 can be arrangedclose to the assembly area 200. The temporary pallet area 270 providesan area on which one or more pallets are temporarily placed before movedto the assembly area 200 or other areas, such as the supply area 104,the output area 108, and the case pick area 109. In addition oralternatively, the case pick area 109 can function as the buffer areaand therefore as an area to which pallets can be transported. In FIG. 2,for example, a pallet 230C may be moved from another area (e.g., thesupply area 104) along a path 250F, and temporarily placed in thetemporary pallet area 270 before it is moved to the assembly area 200.For example, the pallet 230C can be placed in the temporary pallet area270 until one of the cells 220 becomes available which is optimal forpallet arrangement in the assembly area 20 and operation of layerpicking with respect to the pallet 230C thereon. Once the optimal cellis available, the pallet 230C is moved to that cell along a path 250G.

The technology described herein includes one or more of the followingprocesses: (1) driving a first automated pallet mover to move to asupply area in which a plurality of pallets are unloaded and positioned,(2) identifying a target supply pallet from the plurality of pallets inthe supply area, (3) controlling the first automated pallet mover tograsp the target supply pallet, (4) determining a target supply cell onan assembly area, the assembly area defining a plurality of cellsincluding the target supply cell, (5) determining an optimal inboundpath for the first automated pallet mover to reach the target supplycell on the assembly area, (6) driving the first automated pallet moverto move to the target supply cell along the optimal inbound path on theassembly area, (7) controlling the first automated pallet mover to placethe target supply pallet on the target supply cell of the assembly area,(8) controlling a layer picking apparatus to palletize and/ordepalletize between the target supply pallet and a target output pallet,the target output pallet arranged on a target output cell of theassembly area, (9) determining an optimal outbound path for a secondautomated pallet mover to reach the target output cell on the assemblyarea, (10) driving the second automated pallet mover to move to thetarget output cell along the optimal outbound path on the assembly area,(11) controlling the second automated pallet mover to grasp the targetoutput pallet, and (12) driving the second automated pallet mover toexit the assembly area along the optimal outbound path. In certainexamples, the layer picking apparatus includes a layer picking gantryand/or a robotic arm. In certain examples, the first automated palletmover and the second automated pallet mover include automated guidedvehicles. In certain examples, the first automated pallet mover is thesame as the second automated pallet mover. In certain examples, theplurality of cells are defined in a gridded arrangement on the assemblyarea. In certain examples, the target supply cell is determined suchthat the target supply cell is always accessible by the first automatedpallet along at least one path defined through the gridded arrangementof the plurality of cells on the assembly area. In certain examples, thetarget supply cell for the supply pallet and the target output cell forthe output pallet are determined such that every pallet is alwaysaccessible along at least one path defined through the griddedarrangement of the plurality of cells on the assembly area.

FIG. 3 depicts an example system 300 for automatically assemblingpallets of goods in an example warehouse environment. The system 300 canbe similar to the systems 100 and 200 described above with regard toFIGS. 2 and 3 above.

The example warehouse in the example system 300 includes a warehousearea 302 and an automated pallet assembly area 304. The warehouse area302 includes, for example, storage racks for pallets, features to movepallets and out of storage racks (e.g., conveyor belts), a staging areato move pallets in and out of trucks, and/or other features. Thewarehouse area 302 can be, for example, an automated warehouse usingautomated features to store and retrieve pallets, such as conveyor beltsand/or automated vehicles. Alternatively, the warehouse area 30 can be amanually operated warehouse using, for example, forklifts operated byworkers.

The pallet assembly area 304 includes features described throughout thisdocument to automatically build pallets using a layer picking gantrydevice 312 and automated vehicles 310 to position and move palletsthroughout the pallet assembly area 304. In the depicted example,pallets enter the pallet assembly area 304 from the warehouse area 302via a conveyor belt 306 that includes a pallet de-wrapping device 308that is configured to remove wrapping (e.g., cellophane wrapping, shrinkwrap) from the pallets so that layers can be picked by the layer pickinggantry 312. The de-wrapping device 308 can include, for example, a firstmechanism to cut the wrap around the pallet (e.g., laser, blade) and asecond mechanism to grab and pull the wrap from around the pallet (e.g.,robotic arms). The de-wrapping device 308 can be automated and canperform the pallet de-wrapping with little or no human direction. Forexample, the de-wrapping device 308 can use cameras and/or lasers tooptically analyze of the pallets to identify the physical dimensions andshape of the pallet, and to perform its operations without damaging thepallet and/or its contents. Alternatively or in addition, a palletde-wrapping can be manually performed.

Once inside the pallet assembly area 304, the automated vehicles 310 canmove the pallets to various locations throughout the area 304, includingin buffer areas 316 a-c that are around the layer picking gantry device312 and within the layer pick area 314 for the gantry device 312. Thebuffer area 316 a-c can be for storage of pallets that are not currentlybeing used to assemble pallets, but which will be used to assemblepallets in the future. The layer pick area 314 is where pallets fromwhich layers are currently being picked and/or pallets that arecurrently being assembled (e.g., pallets that are receiving layerspicked from other pallets) are positioned. An automated control systemcan be used to identify the pallets to be included in the picking area314 and the buffer areas 316 a-c and the positioning of the palletswithin those respective areas, and to translate those determinationsinto actionable control signals transmitted to the automated vehiclesfor moving pallets throughout the area 304. Such an example controlalgorithm is described below with regard to FIGS. 7A-E.

Once a pallet has been assembled (or is otherwise determined to nolonger be needed in the area 304), the pallet can be transported to anoutbound conveyor belt 318 to transport the pallet out of the area 304.Along the conveyor belt 318 there can be a profiling device 320 that canautomatically scan and analyze the pallet, such as determining thedimensions of the pallet and determining that the pallet is structurallysound (e.g., less than a threshold amount of lean for the stacked goodson the pallet). Once a pallet passes the profiling device 320, it can bewrapped by a pallet wrapping device 322, which can automatically wrapthe pallet in wrapping material (e.g., cellophane wrap, shrink wrap).

In some implementations, the pallet assembly area 304 can include a casepick area 330 similar to the case pick area 109 in FIG. 1. Although notspecifically illustrated in FIG. 3, cases can be transported to/from thecase pick area 330 using automated transportation equipment, such asconveyor belts 318 and/or automated vehicles 310. Manual picking andtransporting can also be used within the case pick area 109 or onto/fromthe automated transportation equipment.

FIG. 4A depicts another example system 400 for automatically assemblingpallets of goods in an example warehouse environment. The system 400 canbe similar to the systems 100, 200, and 300 described above with regardto FIGS. 1, 2, and 3 above.

The example system 400 includes a common conveyor belt 402 to bringpallets into and to transport pallets out of the assembly area, whichincludes the pallet assembly area 408 and the buffer areas 414 a-caround the layer picking gantry device 406. The spacing and positioningof the areas 408 and 414 a-c can be designed and maintained so thatautomated vehicles 404 are able to access each pallet in the areawithout having to first move other pallets. This includes maintainingpathways 412 within the area 408 so that pallets (e.g., pallet 410)within the area 408 can be accessed without first having to move otherpallets. Similarly, the buffer areas 414 a-c can be designated andmaintained such that pallets can readily be accessed, added to, andremoved from the buffer areas 414 a-c without having to move otherpallets.

FIG. 4B illustrates an example system 430 for automatically assemblingpallets of goods in an example warehouse environment. The system 430 canbe similar to the systems 100, 200, 300, and 400 described above withregard to FIGS. 1, 2, 3, and 4A above. The system 430 includes anassembly device 436, an assembly area 438 and one or more buffer areas444 a-d (collectively 444). As described herein, the pallets in thesystem 430 can be transported using one or more automated vehicles 434(e.g., AGVs, SDVs, or other suitable vehicles). The assembly device 436can be a layer picking gantry device, a robotic arm, or other devicesuitable for palletizing or depalletizing process. The assembly device436 can be located at a center of the assembly area 438, or configuredto have the center of the assembly area 438 as a primary location (orreference location) at which the assembly device 436 is positioned atdefault, substantially passes through in operation, or refers to whendetermining routes to travel or move over the assembly area 438.

The assembly area 438 can include a plurality of zones 432 a-c(collectively 432) for arranging different groups of pallets thereon forlayer picking operations. The plurality of zones 432 can be arrangedwith respect to a center of the assembly area 438. In someimplementations, a first zone 432 a (Zone 1) is arranged at the centerof the assembly area 438 and a second zone 432 b (Zone 2) is arranged tosurround the first zone 432 a. For example, at least some of the zones432 can be arranged coaxially. In some implementations, the assemblyarea 438 includes a plurality of cells 442 in a gridded arrangement,each of which is configured to permit for a pallet to be placed thereon.Each of the zones 432 can include one or more cells, and the cells ofthe first zone 432 a are grouped and arranged at the center of theassembly area 438 while the cells of the second zone 432 b are groupedand arranged to surround the cells of the first zone 432 a. For a simpleexample, where the assembly area 438 includes 9 cells in a 3×3 grid, thefirst zone 432 a can be the center cell, and the second zone 432 bincludes 8 cells that surrounds the center cell.

The plurality of pallets 440 can be categorized into multiple groups ofpallets by their attributes, and such groups of pallets can be locatedin different zones of the assembly area 438 in a way to optimize usageof the assembly device 436 and/or the automated vehicles 434, andincrease efficiency in operating the assembly device 436 and/or theautomated vehicles 434. In some implementations, a plurality of pallets440 can be categorized into multiple groups of pallets 440 a-c by theirvelocities or ranges of velocity. For example, a velocity of a palletcan represent how fast the pallet is palletized or depalletized in anassembly area, or represent how long the pallet stays in an assemblyarea (or on its location in the assembly area) before the pallet isremoved from the assembly area (or before it is relocated in theassembly area). The velocity of a pallet increases as the pallet ispalletized or depalletized faster, or as the pallet stays in an assemblyarea (or on its location in the assembly area) for a shorter period oftime. Alternatively, a velocity of a pallet can represent how manylayers of goods are moved onto or out from the pallets per apredetermined period of time. Thus, the velocity of a pallet increasesas more layers of goods are moved onto or out from the pallet over aperiod of time.

For example, a plurality of pallets can be grouped into first velocitypallets 440 a and second velocity pallets 440 b. The first velocitypallets 440 a are pallets having a first velocity or within a firstvelocity range, and the second velocity pallets 440 b are pallets havinga second velocity or within a second velocity range. By way of example,the first velocity pallets 440 a (e.g., slow speed pallets or slowmoving pallets) can have one or more layers of goods to be removed ontoor out from the pallets more than a first threshold number of times pera predetermined period of time, and the second velocity pallets 440 b(e.g., high speed pallets or fast moving pallets) can have one or morelayers of goods to be removed onto or out from the pallets less than thefirst threshold number of times per the predetermined period of time. Inthe illustrated example, the first velocity pallets 440 a can bearranged in the first zone 432 a (Zone 1), and the second velocitypallets 440 b can be arranged in the second zone 432 b (Zone 2). Thisarrangement can permit for the second velocity pallets 440 b (e.g., highspeed pallets or fast moving pallets) to be introduced into and removedfrom the assembly area more quickly than the first velocity pallets 440a (e.g., low speed pallets or slow moving pallets), after palletizing ordepalletizing is complete.

In addition, the assembly area 438 can further include a third zone 432c (Zone 3) which is arranged to surround the second zone 432 b. Forexample, the cells of the third zone 432 c are grouped and arranged tosurround the cells of the second zone 432 b. In some implementations,the third zone 432 c is arranged at a periphery of the assembly area438, as illustrated in FIG. 4B. The third zone 432 c is used for pallets(e.g., slower or absolutely slow pallets) that the assembly device donot have to reach as often and/or fast as it does for fast or slowmoving pallets. For example, some of the plurality of pallets can begrouped into third velocity pallets 440 c having a third velocity or athird velocity range. For example, the third velocity pallets 440 c(e.g., slower/slowest speed pallets or slower/slowest moving pallets)can have one or more layers of goods to be moved onto or out from thepallets less than a second threshold number of times per thepredetermined period of time, and the second threshold number of timesis smaller than the first threshold number of times described above. Insome implementations, the third zone 432 c is configured to have asingle line of cells 442 around the periphery of the assembly area 438.

Although this example illustrates three different zones on the assemblyarea, it is understood that the assembly area can have two differentzones or more than three different zones in similar manners.

In some implementations, the assembly area 438 can be accompanied withthe buffer areas 444 that are designated and maintained such thatpallets can be readily accessed, added to, and removed from the bufferareas 444. The buffer areas 444 can be used to stage pallets 440 d thatare to be transported into the assembly area 438 shortly or as soon ascells for the pallets 440 d become available in the assembly area 438.For example, the buffer areas 444 can be used to buffer with palletsthat are less frequently used (e.g., single use or only a few uses in aday). In alternatively examples, when more SKUs (stock keeping units)are needed than the assembly area can accommodate, the buffer areas 444can be used to buffer those SKUs until they can be picked. In exampleswhere two SKUs are needed but there is only one spot available in theassembly area, pallets for such SKUs can be arranged in the assemblyarea and the buffer areas, and the assembly device (e.g., gantry device,robotic arms, etc.) and/or the automated vehicles (e.g., AGVs, SDVs,etc.) can build the pallets at the same time both in the assembly areaand the buffer areas, or build the pallets in sequence or alternatinglyin the assembly area and the buffer areas.

The buffer areas 444 and the assembly area 438 are configured such thatpallets can be transported from the buffer areas 444 to the assemblyarea 438, and/or from the assembly area 438 to the buffer areas 444,along optimal paths, such as shortest possible routes therebetween, forefficient transportation of pallets. For example, transportation pathsbetween the assembly area 438 and the buffer areas 444 can be straightroutes.

FIG. 4C illustrates an example system 450 for automatically assemblingpallets of goods in an example warehouse environment. The system 450 canbe similar to the system 430 in FIG. 4B, and further similar to thesystems 100, 200, 300, and 400 described above with regard to FIGS. 1,2, 3, and 4A above. To the extent reasonable, the same or similarreference numbers are used for the same or similar elements in FIGS. 4Band 4C. Similarly to the system 430, the system 450 includes theassembly device 436, the assembly area 438 and the buffer areas 444 a-d(collectively 444). In the system 450, the assembly area 438 can includea plurality of subareas 452 a-d (collectively 452), each of which caninclude a plurality of zones 432 for different groups of pallets 440 asdescribed in FIG. 4B. For example, each of the subareas 452 can includefirst and second zones 432 a-b for pallets 440 a-b having differentvelocities. In some implementations, the assembly device 436 can performlayer picking operations for the subareas 452 one-by-one. In otherimplementations, the assembly device 436 can perform layer pickingoperations for the subareas 452 in alternating manners. In yet otherimplementations, a plurality of assembly devices can be used to performlayer picking operations on the subareas 452 in parallel.

In addition, each of the subareas 452 can include the third zone 432 cin the same or similar manner as described in FIG. 4B (e.g., the thirdzone 432 c is arranged at a periphery of the subarea 452). Alternativelyor in addition, the third zone 432 c can be arranged at a peripheral ofthe entire assembly area 438 as illustrated in FIG. 4C.

FIG. 5 depicts another example system 500 for automatically assemblingpallets of goods in an example warehouse environment. The system 500 canbe similar to the systems 100, 200, 300, and 400 described above withregard to FIGS. 2, 3, 4, and 5 above.

The system 500 includes a similar layout and design to the system 300,with a warehouse area 502, a pallet assembly area 504, conveyor belt 506and pallet de-wrapping device 508 to transport and prepare pallets fordisassembly/assembly, automated vehicles 510, buffer areas 516 a-c, anda conveyor belt 518 to transport pallets out of the area 504 along witha pallet profiler 520 and a pallet wrapping device 522. The maindifference between the system 300 and the system 500 is that, instead ofusing a layer pick gantry device 312 as in system 300, multiple layerpicking arms 512 a-d are used in the system 300. The layer picking arms512 a-d can be fixed to a position in the area 504 (e.g., fixed to theground, fixed to the ceiling, fixed to a wall) and, as a result, may notbe able to reach as many pallets to pick from as the layer pick gantrydevice 312, which can move along rails in multiple dimensions (asdescribed above). Accordingly, multiple layer picking arms 512 a-d maybe used (or a single layer picking arm can be used, as well). Palletscan be arranged in picking areas 514 a-d that correspond to each of thelayer picking arms 512 a-d. As discussed above, the positioning ofpallets within the picking areas 514 a-d and the buffer areas 516 a-ccan be designed so that the automated vehicles 510 can access eachpallet without having to move other pallets, which can include leavingpathways around and within each area so that each pallet is accessible.

FIG. 6 depicts an example pallet picking area 600 that can be used withautomated vehicles 602 and a layer picking gantry device (not depicted).The picking area 600 can be similar to the picking areas describedabove, such as the picking/assembly areas 106, 200, 314, and 408. In thedepicted example, the area 600 can include a sufficient number of spacesso that, were pallets to fill each position, some of the internalpallets would be inaccessible by the automated vehicle 602. Accordingly,to maintain accessibility to each position for the automated vehicle602, pathways 604 and 606 can be maintained in the area 600. Suchpathways can be determined by an automated control system, which cancontrol and direct the automated vehicles 602 as well as the pickingdevice.

Such an automated control system can be designed to achieve a variety ofobjectives and/or tasks, such as determining optimal paths for allautomated vehicles 602, making optimal use of the pallets in thepicking/assembly area 600 (e.g., if pallets in the picking/assembly area600 are not being used then place into buffer area), determining andexecuting an optimal exchange ratio of the pallets of the buffer areaand the picking/assembly area 600 (e.g., balance between exchangingpallets between areas (exchanging too frequently can createinefficiencies) and maintaining pallets that are currently being usedwithin the picking/assembly area 600), determining routes that avoidpotential automated vehicle collisions (and providing logic/features onautomated vehicles to permit for autonomous collision avoidance, such asa minimum spacing distance between automated vehicles), putting palletsused to build “like” orders with other pallets for “like” orders tospeed up building like pallets (e.g., minimize the travel time for layerpicking device and increases the throughput of pallets being assembled),and/or creating pallets that only need a layer or two taken off, thentake the part with the greater layer count and use that for the layerpicked pallet (e.g., this can saves time in picking the pallet). Thesetasks/objectives can be achieved using any of a variety of factors, suchas tracking of length of times 612 the pallets are within the pickingarea 600, tracking the density or “filled” positions of the layerpicking area, tracking empty pallets 608, tracking open positions 610,and/or tracking the layers that have been picked, which can ensure thatpallets are being assembled in an optimal position to minimize thegantry head movements.

FIGS. 7A-E are flowcharts of example techniques that can be used as partof an automated control system for pallet assembly using automatedvehicle and automated layer picking devices. The example techniques canbe used to control and optimize the performance of the systems describedthroughout this document, such as those described above with regard toFIGS. 1-6. These techniques can be performed by, for example, thecomputing device 150 and/or other suitable device/system forautomatically determining and controlling the pallet assembly systemsdescribed throughout this document.

Referring to FIG. 7A, an example technique 700 is depicted fortransmitting instructions to the automated vehicles for positioning andmoving pallets to optimize the pallet assembly operations performed by alayer picking device, such as a gantry device and/or a robotic armpicking device. An optimal pallet composition for the picking area andbuffer area(s) is determined (702). An example technique for determiningthat optimal composition is described below with regard to FIG. 7B.Using the current and determined optimal pallet composition for theseareas, identification of pallets to be exchanged between these areas canbe determined (704). The pallets to be exchanged between these areas canbe designated as the pallets to be moved between the areas.

An optimal positioning of pallets in the picking area (706) and thebuffer area (708) can be determined. The optimal pallet positioning inthe picking area and the buffer area can take into account not only thepallets being moved in and out of the area, but can also evaluate theoverall positioning of pallets in the area and may make appropriateadjustments (including to pallets already in those areas) in order tooptimize the overall positioning scheme. An example technique fordetermining pallet positioning in the picking area is provided in FIG.7C. Similarly, an example technique for determining pallet positioningin the buffer area is provided in FIG. 7D.

From the determinations in 706 and 708, the destinations of pallets tobe moved can be determined (710). Using these destinations, routes andsequences of automated vehicles to move the pallets from their currentlocations to the destination locations can be determined (712). Anexample technique for performing this is described with regard to FIG.7E. Once the routes and sequencing of automated vehicle pallet movementsare determined, instructions for the automated vehicle movements can betransmitted to the automated vehicles (714).

In some implementations, the determination of routes and/or sequencingof pallet movements are not static, but dynamically performed tomaintain the routes and/or sequencing to be updated and optimal. Theroutes and/or other logic decisions resulting in a change to the routescan be re-evaluated in real time, periodically, and/or when an eventoccurs (e.g., executed or changed). For example, when an order isreceived or modified, such a new or modified order can causereevaluation of the routes and/or other logic decisions.

Referring to FIG. 7B, an example technique 720 is depicted fordetermining the optimal composition of pallets for the picking area andthe buffer area. Pallets that are currently located in the picking andbuffer areas are identified (722). For the pallets in the picking area,a variety of determinations are made to ensure that the positions in thepicking area are being optimized, including determining a length of timethey have been located in the picking area (724), a density of thepositions in the picking area (726), and identifying any empty palletsor empty positions in the picking area (728). Pallet orders that arebeing assembled currently and for a threshold period of time into thefuture (e.g., next 30 minutes, next hour, next 6 hours, next 12 hour)can be identified (730), including identifying the layers that arerequired to fulfill the orders and the specific pallets (in both thepicking and buffer area) that can be used to fulfill those orders. Usingthe factors determined in 724-730, optimal pallets for the picking areaand the buffer area can be determined (732). With the optimal palletsidentified for each of the picking and buffer area, the pallets thatneed to be exchanged between the areas (difference between currentpallets in areas and optimal pallets identified for areas) can beidentified (734).

Referring to FIG. 7C, an example technique 740 is depicted fordetermining the positioning of pallets in the picking area. The currentpositioning of pallets is identified (742) and the pallets to be locatedin the area (as determined by technique 720) are identified (744).Positions in the picking area to remain open (unoccupied by pallets) inthe picking area to provide a pathway for automated vehicle movement areidentified (746) and pallet order to be assembled over a thresholdperiod of time into the future are identified (748). Pallets withcontents that will be used to assemble the same or similar orders can begrouped together so that they will be near each other within the area(minimize picker travel time and maximize pallet assembly throughput)(750). Using these determinations and factors (742-750), new positioningof pallets in the picking area can be determined (752) and madeavailable for route determination for the automated vehicles (754).

Referring to FIG. 7D, an example technique 760 is depicted fordetermining the positioning of pallets in the buffer area. The currentpositioning of pallets is identified (762) and the pallets to be locatedin the area (as determined by technique 720) are identified (764).Spaces around the buffer area to remain open (unoccupied by pallets) toprovide a pathway for automated vehicle movement are identified (766)and pallet order to be assembled over a threshold period of time intothe future are identified (768). Using the order information, adetermination of the timing, sequence, and eventual positioning ofbuffer pallets for the picking area (when they are moved from the bufferarea to the picking area) is estimated so that they can be positioned inoptimal locations in the buffer area to minimize automated vehicletravel time to move them from the buffer area into the picking area(770). Using these determinations and factors (762-770), new positioningof pallets in the buffer area can be determined (772) and made availablefor route determination for the automated vehicles (774).

Referring to FIG. 7E, an example technique 780 is depicted fordetermining routes and sequencing of those routes to move positionpallets in the buffer and picking areas. Identification of the palletsto be moved, their current positioning, and their destinationpositioning can be determined (782). A sequence of dependent movementscan be determined to place the pallets in their destination locations(784). For example, for a pallet position that is the destination for afirst pallet and that is currently occupied by a second pallet, themovement of the second pallet can be identified as having to occursequentially before movement of the first pallet (first pallet movementis dependent on the second pallet movement occurring earlier in time).Routes to minimize the distance travelled to transport each pallet fromits current position to its destination position can be identified(786), and timing sequences for the routes can be determined (788).Routes and timing sequences can be adjusted in order to avoid collisionsand the maintain a minimum threshold distance between the automatedvehicles (790), and can then be provided for use to control operation ofthe automated vehicles to execute on the determinations (792).

In some implementations, at least some of the technique 780, includingcalculation, adjustment, and/or update of the routes and timingsequences can be performed by automated vehicles on their own withoutinteracting with a remote computing device.

FIG. 7F is a flowchart of an example technique 1700 for palletizing(including depalletizing) in a layer pick area. The technique 1700 caninclude multiple operations. For example, multiple zones (e.g., thefirst, second, and third zones described herein) are determined in alayer pick area (e.g., the assembly area described herein) (1702). Eachof a plurality of pallets is identified as one of multiple palletsgroups (1704). Such multiple pallet groups can be determined by one ormore attributes of pallets, such as velocities representative of, forexample, how fast layers of goods are removed from or loaded ontopallets (e.g., the first, second, and third velocity pallets describedherein). Positions in the layer pick area are identified according toidentification of the pallets (e.g., according to the velocities of thepallets) (1706). Each of the identified positions are included in one ofthe multiple zones according to the attributes of the pallets. Thepallets are placed onto the identified positions in the layer pick area(1708). A layer pick apparatus (e.g., a layer pick gantry, robotic arm,etc.) is operated to palletize and depalletize in the layer pick area(1710). Once the pallitizing/depalletizing is complete for a pallet, thepallet is removed from the layer pick area (1712). The pallet can beremoved using an automated vehicle, such as an AGV, SDV, etc., asdescribed herein.

FIGS. 8A-C depict example systems to control operation of the automatedvehicles using stereoscopic vision.

Referring to FIG. 8A, an example automated vehicle 800 is depicted withstereoscopic imaging devices 802 (e.g., stereoscopic cameras) mounted onthe side of the automated vehicle 800. The automated vehicle 800 mayinclude multiple stereoscopic imaging devices that are positioned on itssides, such as an additional stereoscopic imaging device positioned onan opposing side of the automated vehicle 800. The stereoscopic imagedata 832 can be generated by the automated vehicle 800 and used todetermine a precise location of the automated vehicle 800 within aphysical environment, such as a warehouse. An example system for makingsuch location determination for the automated vehicle 800 can include acentral system 820 that contains a spatial model 822 of the environment(e.g., point cloud of the environment). In some instances, the automatedvehicle 800 can transmit the stereoscopic image data 832 over one ormore networks 830 (e.g., Wi-Fi) to the central system 820, which cangenerate spatial positioning of features (e.g., points) from thestereoscopic image data 832, compare that spatial positioning offeatures to the spatial model 822 to determine the location of theautomated vehicle 800, and then transmit the location information 838back to the automated vehicle 800 (or to other systems used to controloperation of the automated vehicle 800). Alternatively, the spatialmodel can be loaded onto the automated vehicle 800 and thosedeterminations can be made locally on the automated vehicle 800.Techniques, systems, devices, and features for using stereoscopic visionto determine a vehicle's location within a warehouse, which can beapplied to the automated vehicle 800, are described in U.S. Pat. No.10,242,273, entitled TRACKING VEHICLES IN A WAREHOUSE ENVIRONMENT,issued Mar. 26, 2019, the entire contents of which are incorporated byreference.

Referring to FIG. 8B, another example automated vehicle 810 is depicted.In this example, the stereoscopic imaging device 812 is positioned andextends above a top surface of the automated vehicle 810. Such apositioning of the stereoscopic imaging device 812 can provide a highervantage point (higher relative to the ground), which may be used togenerate more spatial positioning features (e.g., points) that can beused to more accurately determine the location of the automated vehicle810 using the spatial model 822.

FIG. 8C illustrates an example automated vehicle 830. The automatedvehicle 830 can be used for the automated vehicles described herein,such as the automated vehicles 140, 310, 404, 434, 800, 1030, etc. Inthis example, the automated vehicle 830 can lift a pallet from theground for transportation without losing flexibility of the automatedvehicle 830 in moving freely in/out and within various areas in awarehouse environment, such as assembly areas, dock areas, case pickareas, etc. The automated vehicle 830 includes a pallet lift structure832 having forks 834 for supporting an underneath of a pallet, and afork lift mechanism 836 for vertically moving the forks 834 with respectto the ground.

In addition or alternatively, one or more pallets can be placed with astand on the ground. The stand is configured to support the pallets at adistance away from the ground so that an automated vehicle or othervehicles can easily engage and lift the pallets for transportation. Forexample, the stand can provide a sufficient room underneath a palletfrom the ground so that an automated vehicle can at least partially moveinto the room, permit for the pallet to be placed thereon, and move outfrom the room for transportation.

FIG. 9 is a block diagram of computing devices 900, 950 that may be usedto implement the systems and methods described in this document, aseither a client or as a server or plurality of servers. Computing device900 is intended to represent various forms of digital computers, such aslaptops, desktops, workstations, personal digital assistants, servers,blade servers, mainframes, and other appropriate computers. Computingdevice 950 is intended to represent various forms of mobile devices,such as personal digital assistants, cellular telephones, smartphones,and other similar computing devices. The components shown here, theirconnections and relationships, and their functions, are meant to beexamples only, and are not meant to limit implementations describedand/or claimed in this document.

Computing device 900 includes a processor 902, memory 904, a storagedevice 906, a high-speed interface 908 connecting to memory 904 andhigh-speed expansion ports 910, and a low speed interface 912 connectingto low speed bus 914 and storage device 906. Each of the components 902,904, 906, 908, 910, and 912, are interconnected using various busses,and may be mounted on a common motherboard or in other manners asappropriate. The processor 902 can process instructions for executionwithin the computing device 900, including instructions stored in thememory 904 or on the storage device 906 to display graphical informationfor a GUI on an external input/output device, such as display 916coupled to high-speed interface 908. In other implementations, multipleprocessors and/or multiple buses may be used, as appropriate, along withmultiple memories and types of memory. Also, multiple computing devices900 may be connected, with each device providing portions of thenecessary operations (e.g., as a server bank, a group of blade servers,or a multi-processor system).

The memory 904 stores information within the computing device 900. Inone implementation, the memory 904 is a volatile memory unit or units.In another implementation, the memory 904 is a non-volatile memory unitor units. The memory 904 may also be another form of computer-readablemedium, such as a magnetic or optical disk.

The storage device 906 is capable of providing mass storage for thecomputing device 900. In one implementation, the storage device 906 maybe or contain a computer-readable medium, such as a floppy disk device,a hard disk device, an optical disk device, or a tape device, a flashmemory or other similar solid state memory device, or an array ofdevices, including devices in a storage area network or otherconfigurations. A computer program product can be tangibly embodied inan information carrier. The computer program product may also containinstructions that, when executed, perform one or more methods, such asthose described above. The information carrier is a computer- ormachine-readable medium, such as the memory 904, the storage device 906,or memory on processor 902.

The high-speed controller 908 manages bandwidth-intensive operations forthe computing device 900, while the low speed controller 912 manageslower bandwidth-intensive operations. Such allocation of functions is anexample only. In one implementation, the high-speed controller 908 iscoupled to memory 904, display 916 (e.g., through a graphics processoror accelerator), and to high-speed expansion ports 910, which may acceptvarious expansion cards (not shown). In the implementation, low-speedcontroller 912 is coupled to storage device 906 and low-speed expansionport 914. The low-speed expansion port, which may include variouscommunication ports (e.g., USB, Bluetooth, Ethernet, wireless Ethernet)may be coupled to one or more input/output devices, such as a keyboard,a pointing device, a scanner, or a networking device such as a switch orrouter, e.g., through a network adapter.

The computing device 900 may be implemented in a number of differentforms, as shown in the figure. For example, it may be implemented as astandard server 920, or multiple times in a group of such servers. Itmay also be implemented as part of a rack server system 924. Inaddition, it may be implemented in a personal computer such as a laptopcomputer 922. Alternatively, components from computing device 900 may becombined with other components in a mobile device (not shown), such asdevice 950. Each of such devices may contain one or more of computingdevice 900, 950, and an entire system may be made up of multiplecomputing devices 900, 950 communicating with each other.

Computing device 950 includes a processor 952, memory 964, aninput/output device such as a display 954, a communication interface966, and a transceiver 968, among other components. The device 950 mayalso be provided with a storage device, such as a microdrive or otherdevice, to provide additional storage. Each of the components 950, 952,964, 954, 966, and 968, are interconnected using various buses, andseveral of the components may be mounted on a common motherboard or inother manners as appropriate.

The processor 952 can execute instructions within the computing device950, including instructions stored in the memory 964. The processor maybe implemented as a chipset of chips that include separate and multipleanalog and digital processors. Additionally, the processor may beimplemented using any of a number of architectures. For example, theprocessor may be a CISC (Complex Instruction Set Computers) processor, aRISC (Reduced Instruction Set Computer) processor, or a MISC (MinimalInstruction Set Computer) processor. The processor may provide, forexample, for coordination of the other components of the device 950,such as control of user interfaces, applications run by device 950, andwireless communication by device 950.

Processor 952 may communicate with a user through control interface 958and display interface 956 coupled to a display 954. The display 954 maybe, for example, a TFT (Thin-Film-Transistor Liquid Crystal Display)display or an OLED (Organic Light Emitting Diode) display, or otherappropriate display technology. The display interface 956 may compriseappropriate circuitry for driving the display 954 to present graphicaland other information to a user. The control interface 958 may receivecommands from a user and convert them for submission to the processor952. In addition, an external interface 962 may be provide incommunication with processor 952, so as to enable near areacommunication of device 950 with other devices. External interface 962may provided, for example, for wired communication in someimplementations, or for wireless communication in other implementations,and multiple interfaces may also be used.

The memory 964 stores information within the computing device 950. Thememory 964 can be implemented as one or more of a computer-readablemedium or media, a volatile memory unit or units, or a non-volatilememory unit or units. Expansion memory 974 may also be provided andconnected to device 950 through expansion interface 972, which mayinclude, for example, a SIMM (Single In Line Memory Module) cardinterface. Such expansion memory 974 may provide extra storage space fordevice 950, or may also store applications or other information fordevice 950. Specifically, expansion memory 974 may include instructionsto carry out or supplement the processes described above, and mayinclude secure information also. Thus, for example, expansion memory 974may be provide as a security module for device 950, and may beprogrammed with instructions that permit secure use of device 950. Inaddition, secure applications may be provided via the SIMM cards, alongwith additional information, such as placing identifying information onthe SIMM card in a non-hackable manner.

The memory may include, for example, flash memory and/or NVRAM memory,as discussed below. In one implementation, a computer program product istangibly embodied in an information carrier. The computer programproduct contains instructions that, when executed, perform one or moremethods, such as those described above. The information carrier is acomputer- or machine-readable medium, such as the memory 964, expansionmemory 974, or memory on processor 952 that may be received, forexample, over transceiver 968 or external interface 962.

Device 950 may communicate wirelessly through communication interface966, which may include digital signal processing circuitry wherenecessary. Communication interface 966 may provide for communicationsunder various modes or protocols, such as GSM voice calls, SMS, EMS, orMMS messaging, CDMA, TDMA, PDC, WCDMA, CDMA2000, or GPRS, among others.Such communication may occur, for example, through radio-frequencytransceiver 968. In addition, short-range communication may occur, suchas using a Bluetooth, WiFi, or other such transceiver (not shown). Inaddition, GPS (Global Positioning System) receiver module 970 mayprovide additional navigation- and location-related wireless data todevice 950, which may be used as appropriate by applications running ondevice 950.

Device 950 may also communicate audibly using audio codec 960, which mayreceive spoken information from a user and convert it to usable digitalinformation. Audio codec 960 may likewise generate audible sound for auser, such as through a speaker, e.g., in a handset of device 950. Suchsound may include sound from voice telephone calls, may include recordedsound (e.g., voice messages, music files, etc.) and may also includesound generated by applications operating on device 950.

The computing device 950 may be implemented in a number of differentforms, as shown in the figure. For example, it may be implemented as acellular telephone 980. It may also be implemented as part of asmartphone 982, personal digital assistant, or other similar mobiledevice.

Additionally computing device 900 or 950 can include Universal SerialBus (USB) flash drives. The USB flash drives may store operating systemsand other applications. The USB flash drives can include input/outputcomponents, such as a wireless transmitter or USB connector that may beinserted into a USB port of another computing device.

Various implementations of the systems and techniques described here canbe realized in digital electronic circuitry, integrated circuitry,specially designed ASICs (application specific integrated circuits),computer hardware, firmware, software, and/or combinations thereof.These various implementations can include implementation in one or morecomputer programs that are executable and/or interpretable on aprogrammable system including at least one programmable processor, whichmay be special or general purpose, coupled to receive data andinstructions from, and to transmit data and instructions to, a storagesystem, at least one input device, and at least one output device.

These computer programs (also known as programs, software, softwareapplications or code) include machine instructions for a programmableprocessor, and can be implemented in a high-level procedural and/orobject-oriented programming language, and/or in assembly/machinelanguage. As used herein, the terms “machine-readable medium”“computer-readable medium” refers to any computer program product,apparatus and/or device (e.g., magnetic discs, optical disks, memory,Programmable Logic Devices (PLDs)) used to provide machine instructionsand/or data to a programmable processor, including a machine-readablemedium that receives machine instructions as a machine-readable signal.The term “machine-readable signal” refers to any signal used to providemachine instructions and/or data to a programmable processor.

To provide for interaction with a user, the systems and techniquesdescribed here can be implemented on a computer having a display device(e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor)for displaying information to the user and a keyboard and a pointingdevice (e.g., a mouse or a trackball) by which the user can provideinput to the computer. Other kinds of devices can be used to provide forinteraction with a user as well; for example, feedback provided to theuser can be any form of sensory feedback (e.g., visual feedback,auditory feedback, or tactile feedback); and input from the user can bereceived in any form, including acoustic, speech, or tactile input.

The systems and techniques described here can be implemented in acomputing system that includes a back end component (e.g., as a dataserver), or that includes a middleware component (e.g., an applicationserver), or that includes a front end component (e.g., a client computerhaving a graphical user interface or a Web browser through which a usercan interact with an implementation of the systems and techniquesdescribed here), or any combination of such back end, middleware, orfront end components. The components of the system can be interconnectedby any form or medium of digital data communication (e.g., acommunication network). Examples of communication networks include alocal area network (“LAN”), a wide area network (“WAN”), peer-to-peernetworks (having ad-hoc or static members), grid computinginfrastructures, and the Internet.

The computing system can include clients and servers. A client andserver are generally remote from each other and typically interactthrough a communication network. The relationship of client and serverarises by virtue of computer programs running on the respectivecomputers and having a client-server relationship to each other.

Referring to FIGS. 10-12, example pallet transportation systems aredescribed, which are configured to transport pallets between differentpositions in a warehouse.

FIG. 10 depicts an example pallet transportation system 1000 in awarehouse 1002. The warehouse 1002 includes a pallet storage area 1003,which can include pallet storage racks 1004 which can be arranged inrows and/or columns and configured to store pallets 1010 in differentlevels. One or more elevators 1006 and rack conveyor belts 1008 are usedto elevate pallets 1010 to different levels and move them into desiredlocations in the racks 1004. In addition or alternatively, one or morecranes and/or other suitable transportation systems can be used in thewarehouse 1002. The warehouse 1012 includes a staging area 1012 (e.g., aloading/unloading area) to move pallets in and out of trucks 1014through doors 1015. For example, manual labor can be used to unloadpallets from trucks 1014 and deliver them onto decks 1016, and pickpallets up from the decks 1016 and load them onto trucks 1014. Inaddition or alternatively, loading/unloading and/or transportation inthe staging area 1012 can be performed using an automated system, suchas automated guided vehicles (automated vehicles) described herein.

The warehouse 1002 that uses the pallet transportation system 1000 canbe of other types. For example, the pallet transportation system 1000can be used in a manual warehouse that has no automated equipment (e.g.,elevators, conveyor belts, automated vehicles, etc.). In other example,the warehouse 1002 can be a cross-docking warehouse in which palletsunloaded in an unloading area (e.g., from inbound trucks, trains, orother vehicles) are directly transported to, and loaded into, outboundtrucks, trains, or other vehicles in a loading area, skipping a storagearea. Such outbound trucks, trains, or other vehicles can be loaded witha variety of pallets or items that are consolidated and/or regroupedfrom pallets or items from one or more inbound trucks, trains, or othervehicles.

The warehouse 1002 further includes a pallet transportation area 1020 inwhich the pallet transportation system 1000 operates to automate andoptimize transportation of pallets between the staging area 1012 and thepallet storage area 1003. The pallet transportation system 1000 includesautomated guided vehicles (automated vehicles) 1030 to transport pallets1010 in the pallet transportation area 1020. Automated vehicles 1030 areconfigured similarly to the automated vehicles 140, 310, 404, 434, 800,and 830. For example, automated vehicles are configured to automaticallynavigate between the staging area 1012 and the pallet storage area 1003,and are capable of picking up, moving, and dropping off pallets.

The pallet transportation system 1000 includes a computing device 1050for controlling automated vehicles 1030 and/or other devices and systemsin the warehouse 1002. Although a single computing device 1050 isillustrated and primarily described herein, multiple computing devicescan be configured to perform same or similar functions. The computingdevice 1050 is configured to communicate with automated vehicles 1030and/or other devices and systems (e.g., elevators 1006, rack conveyorbelts 1008, etc.), and manage and optimize transportation of pallets inthe warehouse 1002.

The pallet transportation system 1000 is configured to optimizeoperation of automated vehicles 1030 in the warehouse 1002 using variousalgorithms. Algorithms can be configured to calculate a plurality ofpossible routes 1060 for each automated vehicle from a start location toan end location, and determine an optimal route among them. For example,algorithms can be configured to choose a shortest route for at least oneof the automated vehicles. In addition or alternatively, algorithms canbe configured to minimize the number of cross-overs of the routes takenby multiple automated vehicles, thereby reducing the likelihood ofcollision between automated vehicles. In addition or alternatively,algorithms can be configured to optimize the timing of operation ofrespective automated guided vehicles, thereby reducing the likelihood ofcollision between automated vehicles. In addition or alternatively,algorithms can be configured to maximize the speed of at least one ofthe automated vehicles. In addition or alternatively, algorithms can beconfigured to minimize the time required to complete a particularproject of moving pallets in a warehouse.

FIG. 11 depicts another example pallet transportation system 1100 in awarehouse 1002. The system 1100 can be similar to the system 1000described herein with regard to FIG. 10, except that the staging area1012 can optionally include a plurality of staging conveyor belts 1070to automatically deliver pallets to the pallet transportation area 1020.The staging conveyor belts 1070 can be arranged and routed from thedecks 1016 to convey pallets between the decks 1016 and the pallettransportation area 1020.

FIG. 12 is a flowchart of an example technique 1200 that can be used aspart of the pallet transportation system of FIGS. 10 and 11. Thetechnique 1200 is designed to determine optimal routes to move palletsin a warehouse, such as routes between a staging area (e.g., palletloading/unloading area) and a pallet storage area (e.g., pallet storageracks). At 1202, identification of the pallets to be moved, theircurrent positioning, and their destination positioning can bedetermined. At 1024, optimal routes are determined for moving pallets totheir destination positions. For example, optimal routes can bedetermined by identifying routes that provide minimum crossoverstherebetween when the pallets are transported to their destinationpositions along those routes (1220), by identifying fastest routes formoving pallets to their destination positions (1222), by identifyingshortest routes for moving pallets to their destination positions(1224), and/or by identifying routes that result in fastest completionof a project of moving entire pallets in desired manner (1226). At 1206,once optimal routes are determined, timing sequences for the routes canbe determined. At 1208, routes and timing sequences can be adjusted inorder to avoid collisions and maintain a minimum threshold distancebetween the automated vehicles. At 1210, such adjusted routes andtimings can then be provided for use to control operation of theautomated vehicles to execute on the determinations.

The automated pallet assembly technology described throughout thisdocument can, additionally and/or alternatively, be implemented usingautomated vehicles that retain and support pallets (instead of droppingpallets off on the floor/ground, a stand, or other support) as they arebeing accessed, processed, assembled, disassembled, and/or having otheroperations performed on them by other devices, such as an gantry,robotic arm, and/or other device. For example, an automated vehicle 310can be directed to pick-up, support, and move a pallet into a particularposition in the layer pick area 314 and then stay in that position withthe pallet as the pallet is assembled/disassembled by the layer pickinggantry device 312. The automated vehicle 310 can then be directed tomove with the pallet out of the layer pick area 314 once current use ofthe pallet has been completed. Such a configuration of retaining palletson the automated vehicles while they are being accessed by other devicescan be used for some or all pallets within a particular area, and can becombined with techniques that instead drop-off pallets for processing.Retaining pallets on automated vehicles while the pallets are beingaccessed can permit for more rapid movement of pallets in and out of aprocessing area (e.g., layer pick area 314), but may use a larger numberof automated vehicles within a particular area to accomplish theseefficiencies. Additional and/or alternate advantages may also beprovided.

While this specification contains many specific implementation details,these should not be construed as limitations on the scope of thedisclosed technology or of what may be claimed, but rather asdescriptions of features that may be specific to particular embodimentsof particular disclosed technologies. Certain features that aredescribed in this specification in the context of separate embodimentscan also be implemented in combination in a single embodiment in part orin whole. Conversely, various features that are described in the contextof a single embodiment can also be implemented in multiple embodimentsseparately or in any suitable subcombination. Moreover, althoughfeatures may be described herein as acting in certain combinationsand/or initially claimed as such, one or more features from a claimedcombination can in some cases be excised from the combination, and theclaimed combination may be directed to a subcombination or variation ofa subcombination. Similarly, while operations may be described in aparticular order, this should not be understood as requiring that suchoperations be performed in the particular order or in sequential order,or that all operations be performed, to achieve desirable results.Particular embodiments of the subject matter have been described. Otherembodiments are within the scope of the following claims.

1-20. (canceled)
 21. A method for automatically assembling pallets of goods, the method comprising: identifying a target supply pallet among a plurality of pallets, the target supply pallet including supply goods available for transfer to other pallets; controlling a first automated pallet mover to place the target supply pallet in an assembly area that is accessible by a layer picking apparatus, wherein the first automated pallet mover is mobile and is configured to move in and out of the assembly area, wherein the layer picking apparatus is affixed to a support structure and is configured to reach pallets located within the assembly area; controlling the layer picking apparatus to transfer at least a portion of the supply goods from the target supply pallet to a target output pallet, the target output pallet positioned at a target output location within the assembly area; determining an optimal outbound path for a second automated pallet mover to reach the target output location within the assembly area; and controlling the second automated pallet mover to move the target output pallet along the optimal outbound path and exit the assembly area with the target output pallet.
 22. The method of claim 21, wherein the layer picking apparatus includes at least one of a layer picking gantry or a robotic arm.
 23. The method of claim 21, wherein the first automated pallet mover and the second automated pallet mover include automated vehicles.
 24. The method of claim 21, wherein the first automated pallet mover is the same as the second automated pallet mover.
 25. The method of claim 21, wherein the assembly area includes a plurality of cells that are defined in a gridded arrangement, the target output location being selected from the plurality of cells.
 26. The method of claim 25, wherein the first automated pallet mover is controlled to place the target supply pallet at a target supply location of the assembly area; and wherein the target supply location is determined such that the target supply location is always accessible by the first automated pallet along at least one path defined through the gridded arrangement of the plurality of cells on the assembly area.
 27. The method of claim 26, wherein the target supply location for the supply pallet and the target output location for the output pallet are determined such that every pallet is always accessible along at least one path defined through the gridded arrangement of the plurality of cells on the assembly area.
 28. The method of claim 26, further comprising: determining that the target supply pallet is a first pallet having one or more layers of goods to be moved onto or out from the first pallets less than a first threshold number of times per a predetermined period of time; and determining the target supply location in a first zone of the assembly area.
 29. The method of claim 28, further comprising: determining that the target supply pallet is a second pallet having one or more layers of goods to be moved onto or out from the second pallets more than the first threshold number of times per the predetermined period of time; and determining the target supply location in a second zone of the assembly area, the first zone being at least partially surrounded by the second zone.
 30. The method of claim 29, further comprising: determining that the target supply pallet is a third pallet having one or more layers of goods to be moved onto or out from the third pallets less than a second threshold number of times per the predetermined period of time, the second threshold number of times being smaller than the first threshold number of times; and determining the target supply zone in a third zone of the assembly area, the second zone being at least partially surrounded by the third zone.
 31. A system for automatically assembling pallets of goods, the system comprising: an assembly area defining a first zone and a second zone, the first zone being at least partially surrounded by the second zone; one or more automated pallet movers configured to place first pallets in the first zone and second pallets in the second zone, the first pallets having one or more layers of goods to be moved onto or out from the first pallets less than a first threshold number of times per a predetermined period of time, and the second pallets having one or more layers of goods to be moved onto or out from the second pallets more than the first threshold number of times per the predetermined period of time; and a layer picking apparatus configured to transfer at least a portion of goods among the first pallets and the second pallets.
 32. The system of claim 31, wherein the assembly area further includes a third zone, the second zone being at least partially surrounded by the third zone, wherein the one or more automated pallet movers are configured to place third pallets in the third zone, the third pallets having one or more layers of goods to be moved onto or out from the third pallets less than a second threshold number of times per the predetermined period of time, the second threshold number of times being smaller than the first threshold number of times, and wherein the layer picking apparatus is configured to transfer at least a portion of goods among the first pallets, the second pallets, and the third pallets.
 33. The system of claim 31, wherein the one or more automated pallet movers are configured to move the first pallets from a storage area to the first zone of the assembly area, and wherein the one or more automated pallet movers are configured to move the second pallets from the storage area to the second zone of the assembly area.
 34. The system of claim 32, wherein the third zone is arranged on a periphery of the assembly area.
 35. The system of claim 32, wherein the one or more automated pallet movers are configured to move the third pallets between the third zone of the assembly area and a buffer area, the buffer area disposed at least partially around the assembly area.
 36. The system of claim 35, wherein the automated pallet movers move along straight routes between the third zone of the assembly area and the buffer area.
 37. The system of claim 31, wherein the assembly area includes a plurality of cells in a gridded arrangement.
 38. The system of claim 31, wherein the layer picking apparatus includes a layer picking gantry.
 39. The method of claim 31, wherein the automated pallet movers includes AGV and/or SDV.
 40. The method of claim 31, wherein the automated pallet movers are configured to remove the first pallets from the first zone of the assembly area, and configured to remove the second pallets from the second zone of the assembly area. 